Second cycle hysteresis

Thus we see the pattern reported in Fig. 4.S2 is confirmed and greatly extended in its reach. For most of the materials in the present study there is a common linear relationship between second cycle hysteresis and second cycle work input, and this... 

In second and subsequent load cycles, however, in which the Mullins effect was observed, a remarkable degree of uniformity of response was discovered. A unique linear relation was obtained by us, between second cycle hysteresis and second cycle... 

Fig.3. Martensitic transformation hysteresis loops, second cycle, heating rate 30 K/min.

In volume versus radius plots for second cycles, during which no entrapment occurs, hysteresis vanishes when the correct contact angles are employed, as shown in Fig. 12.2. Hysteresis, exhibited in a first intrusion-extrusion cycle, is due solely to entrapment of mercury when the correct contact angles are employed. 

Intrinsic hysteresis is a direct result of surface configuration change, which occurs as a result of wetting the surface with water. The plates were purposely immersed to a deeper immersion depth in the second cycle to observe the extent of intrinsic hysteresis. Significant surface configuration change affects the calculated contact angles on immersion and emersion, which violates the assumption of... 

Figure 26.17 Effect of plasma treatment on the intrinsic hysteresis, which is the difference in second cycle immersion line and the first cycle immersion line, (AC/L) = (C/Llu 2 — Fj T)D,a,i intrinsic hysteresis is directly proportional to the extent of surface configuration change of the surface state.

Also shown is the initial stress 0-300%. For comparison, the table also shows the residual elongation and relative hysteresis in first and second cycles of elongation at the same rate ffjjj and [61]. 

Fig. 4.37 Hysteresis versus work input for second cycle load/unload to increasing emax, in the pseudo-cycUc experiments of Phase 2. Symbols are as in Fig. 4.24. The two dashed lines are linear regressions through data for sub-sets of the materials A (all materials except PU7 and PUS), and B (PU7 and PUS)...

Fig. 3.22 Negative AV hysteresis. Negative AV hysteresis has been employed in order to maintam ventricular pacing in conditions snch as hypertrophic cardiomyopathy. The PV interval is 120 ms in the first cycle. Intrinsic conduction has spontaneously become faster, resulting in a shortened PR interval of 100ms in the second cycle. The AV interval is automatically shortened by 20 to 80ms in order to maintam ventricular pacing (asterisks).

The changing of hysteresis loops due to cycling is shown in Figs. 7.16 and 7.17. All cracks start on the cyclel line. Once a shear stress is exceeded, unloading starts and proceeds along a line parallel to the dotted line A-B. The second cycle is reached when A-B intercepts a line. This process continues. 

Aluminum s corrosive behavior was evaluated in several PILs, for example, [N(Tf)2]"-based PILs [120]. Figure 7.17 shows cyclic voltammograms of an aluminum electrode in [HN llNITfl l from the first to the fourth cycle [120]. The first cycle illustrates a hysteresis loop initiated at about 0.25 V vs. Ag with a large irreversible current peak (1 mA cm" ) at about 1.1 V vs. Ag. For the second cycle, and the following, the initiation potential of the hysteresis loop was significantly shifted to the more anodic side (1.25 V vs. Ag), while the current sharply deCTeased (0.1 mA cm" ). A1 passivation could be achieved in this PIL electrolyte from the second cyclic voltammogram. 

Results with a set of samples stretched only once (designated as U ) and another set of samples stretched again for the second time after initial stretching and following relaxation (designated as 2 ) are presented in Table 1. The purpose of this second cycle was to determine the hysteresis effects. It is observed that in all cases, modulus decreased upon subsequent loading cycles. However, such reduction was very small... 

A typical example, from the extensive study by Kamakin on an alumina-silica gel, is shown in Fig. 3.32. When the mercury pressure was reduced to 1 atm at the end of the first cycle, 27 per cent of the intruded mercury was retained by the sample a second intrusion run followed a different path from the first, whereas the second extrusion curve agreed closely with the first. Change in f re structure of the kind described above could perhaps account for the difference between the two intrusion curves, but could not explain the reproducibility of the remainder of the loop. There is no doubt that hysteresis can exist in the absence of structural change. 

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